GSO filters are made of high quality, solid plane parallel glass with excellent homogeneity. They are anti-reflection coated to prevent glaring and ghosting. All eyepiece filters are threaded to fit GSO and most other manufacturers 1.25" eyepieces and offer a full 26mm clear aperture.

#11 Yellow Green - 78% VLT

Yellow-Green helps to bring out dark surface detail on Jupiter and Saturn, darkens the maria on Mars, and improves visual detail when viewing Neptune and Uranus through large telescopes.